{
  "id": 3151535,
  "title": "A massive collision 10 billion years ago turned our galaxy, the Milky Way, upside down.\nThe galactic smash-up, which involved a large spiral galaxy, occurred 10 billion years ago when the universe was just 4.6 billion years old.\n\nOur galaxy, the Milky Way, is thought to have formed 13.6 billion years ago, not long after the Big Bang.\n\nThe collision is believed to have involved a large spiral galaxy, which has been named the Gaia-Enceladus galaxy.\n\nThe Milky Way was largely made up of stars that were born in the early universe, and it had a distinctive shape, with a large bulge of older stars at its centre and a disk of younger stars.\n\nBut 10 billion years ago, the universe was just 4.6 billion years old, and the Milky Way had a very different structure.\n\nIt had a large disk of stars, gas and dust, but not much of a bulge.\n\nThe collision with the Gaia-Enceladus galaxy changed everything.\n\nThe impact was so violent that it threw the Milky Way's stars, gas and dust into chaotic motion.\n\nThe galaxy was turned 90 degrees on its side, and its stars, gas and dust were flung out into space.\n\nThe stars that had made up the Milky Way's disk were scattered, some moving inward to join the bulge, while others were flung outward into the galaxy's halo.\n\nThe collision is thought to have played a key role in creating the galaxy we see today.\n\nThe distinctive bulge of older stars at the centre of the Milky Way is thought to have formed from the debris of the collision.\n\nThe stars that make up the bulge are mostly older, redder and fainter than the stars in the disk.\n\nThe study, published in the journal Nature, used data from the European Space Agency's Gaia spacecraft.\n\nGaia has been orbiting the L2 Lagrange point, a gravitationally stable location about 1.5 million km from Earth, since 2013.\n\nThe spacecraft has been mapping the positions and movements of 1.6 billion stars in the Milky Way.\n\nThe study's lead author, Dr. Diederik Kruijssen, of the University of Heidelberg, said: \"The Milky Way is a large spiral galaxy with a rather unusual shape.\"\n\nHe said that the collision had \"reshaped\" the galaxy, creating the distinctive bulge of older stars.\n\nDr. Kruijssen said that the study had provided \"the most detailed picture yet of the Milky Way's evolution\".\n\nThe study's findings have provided new insights into the history of the Milky Way and the role that collisions have played in shaping the galaxy.\n\nThe research has also raised new questions about the formation and evolution of galaxies.\n\nThe study's co-author, Dr. Maria-Rosa Cioni, of the INAF Observatory in Italy, said: \"The Gaia spacecraft has provided a wealth of data about the Milky Way.\"\n\nShe said that the study had shown that the collision had \"profoundly changed\" the galaxy.\n\nThe study's findings are an important reminder of the dynamic nature of galaxies and the role that collisions play in shaping their evolution.",
  "url": "https://urgent.news/2026/08/24/100-90",
  "topic": "world",
  "section": "World",
  "published": "2026-08-24T22:55:17.000Z",
  "source": {
    "name": "Hankyoreh",
    "slug": "hankyoreh",
    "url": "https://www.hani.co.kr/arti/science/science_general/1274453.html"
  },
  "original_language": "ko",
  "account": null,
  "summary": null,
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}